Dry battery



lJan. 4, 1927. 1,613,585

H. M. ROSENDAL DAM DRY BATTERY Filed August 14. 1923 lll Cil

Patented Jan. 4, 1927.

UNITED STATES'4 PTENT OFFICE. i

, HENRY M. ROSENDAL DAM, 0F ASTORIA, NEW YORK, ASSIGNOB T0 HEINRICH GAT- TIKER-TANNER, OF RAPPEBSWIL ST. "GALL, SWITZERLAND.

DRY BATTERY.

application mea mgm 14, 192s. sentirmi.' maas. l

This invention relates to dry batteries of the kind in which each unit is in the form of a plate, and each plate being composed of electrodes in-plate form between which an electrolyte is confined. l l.

The general object of ythe invention is to provide a more eiiicient plate battery than is obtainable by following the prior art. It is also an object of the invention to provide an improved method for making such unit plates whereby greater efiiciencyl electrically as Well as many advantages in the manufacture itself may be obtained. y

My invention, therefore, is embodied in a dry battery unit and method for making the same as hereinafter set forth and as illustrated in the accompanying drawing in whichy Fig. 1 is a Vsectional view of a plate unit embodying my invention; y

Fig. 2 is a face view of said plate unit with parts broken away; and y Fig. 3 is a detail View illustrating a modification.

In making the plate unit which in itself constitutes a battery, the following method or process is carried out.

As a first step a depolarizing mixture is prepared in powder form, said mixture consist-ing of manganese, graphite and sal ammoniac in varying proportions depending upon the service to be obtained from the battery. The mixture is moistened with water or a suitable binder and compressed into plate form in a mold.

The plate remains in the mold and on top of it there is placed a layer of graphite, pulverized, which has been impregnated with an iinpregnating material, such for instance as melted resin, bees wax, ceresin or like substances. The graphite layer is then compressed on top of the depolarizing .mix' ture plate.

The graphite is saturated with the impregnatng material aforesaid to such-an extent that it will form a plate when cornpressed, which shall be both impervious and conductive to an extent to permit the maximum current, also known as a short circuit current, to pass through the plate.

The plate is then removed from the mold and placed in an oven on which the binder is baked to make the graphite absolutely impervious. The plate is-` then cooled, and

positive or carbon electrode In the drawing the two elements dev scribed are marked respectively 1 vfor the depolarizing mixture plate and 2 for the graphite plate.

Thereafter a conducting coating is ap- Vplied to the graphite plate. This may .be

done galvano plastically and the plate coated with copper. This,'however, is a process which requires extreme care, 'complicated apparatus andpcannot always be carried out successfully, I have found that excellent results are obtained by applying a thin coat of a suitable binder 3 to the graphite and then pressing a sheet of conductlng metal foil 4 onto the plate. The -binderbeing very thin, it is illustrated in the drawing by a heavy line 3. The foil may be of usual commercial thickness. As stated the foil is applied under pressure, for instance by again placing the plate in the mold, in or` der to obtain intimate p contact between the graphite and the foil.

As a modification, I may use metal screen wire s ee Fig. 3, for pressing the foi] 6 into intimate contact with the graphite. It gives excellent results. v

The edges of the plate are then bound withv paraffin to make it impervious.

Thereafter a piece of fabric 7 'is laid on the depolarized mixture plate and a paper frame 8 is placed over the edges of the cloth.

In order to cause the depolarizing mix-` ture to respond to electrochemical action it must be moistened. A solution of sal ammoniac and zinc chloride produces the desired effect'. The solution is conveniently applied to the fabric from which the solution then 'soaks into the depolarizing mixtureplate.

The negative element of the battery is in the form of a dished plate of zinc 9 which is filledwith an electrolyte 10 in paste form and composed of sal ammoniac, zinc, chloride and bichloride of mercury, or other suitable solution to which an organic substance such for instance as corn starch, has been added to form a paste. It will be noted that the zinc electrode serves as a convenient means me- Vmi chanically for containing and applying the electrolyte. The flanges 11 of t e-zinc element fit snugly against the separator element 8, that 1s the paper frame. -The electrolytic paste also serves as a binding means between the fabric 7 and the zinc.

Thereafter the plate is finally sealed up by an edging 12 of paraffin, wax or the like, which of course merges with the previous applications of like substances, hence the sealing member is designated as one element 12.

It will be clear from the foregoing description and the drawing, that a novel, greatly improved and highly efiicient dry battery plate'has been provided in accordance with the invention, and also that a novel process or method of manufacture has been devised in order to obtain quantity produc tion and greater electrical capacity and efficiency.

The invention distinguishes over the prior art in roviding a distinct separate graphite plate aked to a hardness resulting .in greater density, producing .greater capaclty per unit of volume and weight. The fabric serves as a separating means preventing disintegration of the depolarizing mixture.

The finished plate is of course a. battery in itself. As many plates as may be required for a given output may -be assembled, one plate alongside of the other, with the opposed elements in contact and contained in a convenient box. 1f any one plate unit becomes defective, it may be quickly and easily removed and a new one inserted. Tapping the battery for different voltages` is also an easy matter. The absence, obvious- 1y so, of sol ered or mechanical connections between cells is also a marked advantage. This is especially noteworthy when the battery is used in connection with radio apparatus.

Having thus described my invention with particularity with reference to the preferred embodiment of the same and having referred to some of the possible modifications thereof, it will be obvious to those skilled in the art, 'after understanding my invention, that other changes and modifications may be made therein without departing from the spirit and scope of my invention, and 1 aim in the appended claims to cover such changes and mo the invention.

I claim.

1. A dry battery unit comprising a carbon plate electrode consisting of two layers of different consistencies pressed together andafterwards baked to thereby form an integral unit, a metallic conducting covering on one side intimately atttached thereto, a metallic plate electrode of opposite polarity adjacent the other side with a cavity provided between the said electrodes, an electrolyte contained in said cavity and a porous separating element interposed between said electrolyte and said carbon electrode.

A dry battery unit comprising a carbon electrode consisting of two layers of different consistencies baked together and having a metallic conducting foil pressed partly into one surface of said electrode, a metallic plate electrode ofopposite polarity adjacent the other surface of said carbon electrode forming a cavity between said electrodes, an electrolyte in said cavity and a separating element between said electrolytt` and .said carbon electrode.

3. In a. dry battery, the combination of a plate electrode of carbonaceous material and a metallic conducting foil providing a substantially continuous surface attached thereto with numerous portions of said foil interspersed throughout its areal indented into said surface of said electrode, whereby said electrode is provided with an external metallic contact surface.

' 4. In a dry battery, the combination of a plate electrode of carbonaceous material and ifications as are withinthe scope of `afmetallic conducting foil attached thereto with portions of said foil embedded in one face of said electrode, providing a surface comprising numerous alternate indentations and protuberances, whereby said foil is molded into intimate contact with said carbonaceous material and presents a contact face for forming an electrical connection with said electrode.

Signed at New York city, in the county and State of New York, this 2nd day of July, A. D. 1923.

HENRY M. ROSENDAL DAM. 

